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原文传递 Evaluation of Fiber-Reinforced Unbonded Overlay

题名：	Evaluation of Fiber-Reinforced Unbonded Overlay
作者：	Tim Cboinacld, P.E.
关键词：	Fiber-reinforced concrete (FRC), unbonded overlay, transverse joint spacing, diamond grinding, profilograph, IRI, transverse cracking, friction, polyolefin fibers, steel fibers
摘要：	Fiber-reinforced concrete (FRC) is a composite material consisting of Portland cement concrete (PCC) and discontinuous natural, steel or plastic fibers. The inclusion of fibers in concrete results in improved energy absorbing characteristics of the concrete. Energy absorption is directly or indirectly related to properties such as crack propagation resistance, ductility, impact resistance, fatigue performance and durability. A concrete unbonded overlay was constructed on 1-29 in Atchison county. Eight test sections were established in the unbonded overlay. Three of the test sections were reinforced with steel fibers, three of the test sections were reinforced with polyolefin fibers and two of the test sections were non-reinforced PCC. There were fiber-reinforced test sections 9 ” , 6 ” and 5 ” thick for each type of fiber reinforcement. Transverse joint spacing varied in the fiber- reinforced sections fix)m 15 ’ to 200 ’ . The two non-reinforced PCC test sections were 9 ” and 11 ” and all transverse joints were spaced 15 ’ . The overlay was diamond ground at least 21 days after construction to provide the finished texture. The profilograph readings of the finished pavement measured less than 11 in7/mile with a zero blanking band. The International Roughness Index (IRI) averaged 67. Both of these measures are indicative of very smooth pavement. The compressive and flexural strength of polyolefin fiber-reinforced samples were slightly lower than the non- reinforced concrete. The compressive and flexural strength of the steel fiber-reinforced concrete were comparable to the non-reinforced concrete. Some transverse cracking has appeared in the fiber-reinforced sections of the unbonded overlay. In general, more cracking has developed in the steel fiber-reinforced sections than the polyolefin fiber-reinforced sections. Thinner sections exhibited more cracking than the thicker sections and longer panels exhibited more cracking than shorter panels.
报告类型：	科技报告